Man is thus unique, with some other primates, in having adrenals that secrete large amounts of the precursor steroids dehydroepiandrosterone sulfate (DHEA-S) and dehydroepiandrosterone (DHEA) which are converted into androstenedione (4-dione) and then into active androgens and/or estrogens in peripheral tissues (Labrie et al., In: Important Advances in Oncology. Edited by V. T. de Vita, S. Hellman, S. A. Rosenberg. J. B. Lippincott, Philadelphia, 193-217, 1985; Labrie, Mol. Cell. Endocrinol., 78: C113-C118, 1991; Labrie, et al., In Signal Transduction in Testicular Cells. Ernst Schering Research Foundation Workshop. Edited by V. Hansson, F. O. Levy, K. Taskxc3xa9n. Springer-Verlag, Berlin-New York (Suppl. 2), pp. 185-218, 1996; Labrie et al., Steroids, 62: 148-158, 1997). In a recent study (Labrie, et al., J. Clin. Endocrinol. Metab., 82: 2403-2409, 1997), we have described a dramatic decline in the circulating levels of dehydroepiandrosterone (DHEA), DHEA-sulfate (DHEA-S), androst-5-ene-3xcex2,17xcex2-diol (5-diol), 5-diol-S, 5diol fatty acid esters, and androstenedione in both men and women between the ages of 20 and 80 years.
Despite the marked fall in endogenous androgens in women during aging, the use of androgens in post-menopausal women has been limited mainly because of the fear of an increased risk of cardiovascular disease as based upon older studies showing an unfavorable lipid profile with androgens. Recent studies, however, have shown no significant effect of combined estrogen and androgen therapy on the serum levels of cholesterol, triglycerides, HDL, LDL, and HDL/LDL ratio when compared to estrogen alone (Sherwin et al., Am. J. Obstet. Gynecol., 156: 414-419, 1987). In agreement with these observations, we have shown that DHEA, a compound having a predominantly androgenic influence, has apparently no deleterious effect on the serum lipid profile (Diamond, et al., J. Endocrinol., 150: S43-S50, 1996), Similarly, no change in the concentrations of cholesterol, its subfractions or triglycerides, over a treatment with estradiol alone has been observed after 6 months of therapy with estradiol+testosterone implants (Burger et al., Br Med. J. Clin. Res. Ed., 294: 936-937, 1987). It should be mentioned that a study in man has shown an inverse correlation between serum DHEA-S and low density lipoproteins (Parker et al., Science, 208: 512-514, 1980). More recently, a correlation has been found between low serum testosterone and DHEA and increased visceral fat, a parameter of higher cardiovascular risk (Tchernof et al., Metabolism, 44: 513-519, 1995).
Five-diol is a compound biosynthesized from DHEA through the action of reductive 17xcex2-hydroxysteroid dehydrogenase (17xcex2-HSD) and is a weak estrogen. It has an 85-fold lower affinity than 170estradiol (E2) for the estrogen receptor in rat anterior pituitary gland cytosol (Simard and Labrie, J. Steroid Biochem., 26: 539-546, 1987), further confirming the data obtained on the same parameter in human myometrial and breast cancer tissue (Kreitmann and Bayard, J. Steroid Biochem., 11: 1589-1595, 1979; Adams et al., Cancer Res., 41: 4720-4926, 1981; Poulin and Labrie, Cancer Res., 46: 4933-4937, 1986). However, at concentrations well within the range of the plasma levels found in adult women, 5-diol enhances cell proliferation and progesterone receptor levels in human mammary tumor ZR-75-1 cells (Poulin and Labrie, Cancer Res., 46: 4933-4937, 1986) and increases the estrogen-dependent synthesis of the 52 kDa glycoprotein in MCF-7 cells (Adams et al., Cancer Res., 41: 4720-4926, 1981).
As mentioned above, it is known that the serum levels of DHEA, DHEA-S and 5-diol decrease with age and correspondingly, that there is a dramatic age-dependent reduction in the formation of androgens and estrogens in peripheral target tissues. Such changes in DHEA-S and DHEA secretion result in a marked decrease in the biochemical and cellular functions stimulated by sex steroids. As a result, DHEA and DHEA-S have recently been used in the treatment of a variety of conditions which are associated with decrease and/or imbalance in the levels of sex steroids.
Osteoporosis, a condition which affects both men and women, is associated with a decrease in androgens and estrogens. Estrogens have been shown to decrease the rate of bone degradation while androgens have been shown to build bone mass. However, estrogen replacement therapy commonly used against osteoporosis requires the addition of progestins to counteract the endometrial proliferation and the risk of endometrial cancer induced by estrogens. Moreover, since both estrogens and progestins are thought to increase the risk of breast cancer (Bardon et al., J. Clin. Endocrinol. Metab., 60: 692-697, 1985; Colditz et al., N. Engl. J. Med., 332: 1589-1593, 1995), the use of estrogen-progestin replacement therapy is accepted by a limited number of women and, usually, for too short periods of time.
Several studies suggest that osteoporosis is a clinical manifestation of androgen deficiency in men (Baran et al., Calcif. Tissue Res. 26: 103-106, 1978; Odell and Swerdloff, West J. Med. 124: 446-475, 1976; Smith and Walker, Calif. Tissue Res. 22 (Suppl.): 225-228, 1976). Androgen therapy, as observed with nandrolone decanoate, has been found to increase vertebral bone mineral density in postmenopausal women (Need et al., Arch. Intern. Med., 149: 57-60, 1989). Therapy of postmenopausal women with nandrolone increased cortical bone mineral content (Need et al., Clin. Orthop. 225: 273-278, 1987). Androgenic side-effects, however, were recorded in 50% of patients. Such data are of interest since while almost all present therapies are limited to a reduction of bone loss, an increase in bone mass was found with the use of the anabolic steroid nandrolone. A similar stimulation of bone formation by androgens has been suggested in a hypogonadal male (Baran et al., Calcif. Tissue Res. 26: 103, 1978). A stimulation of bone formation in postmenopausal women treated with DHEA for 12 months is reported in labrie et al. (J. Clin. Endocrinol. 82: 3498-3505, 1997).
DHEA (450 mg/kg, b.w., 3 times a week) markedly delayed the appearance of breast tumors in C3H mice which were genetically bred to develop breast cancer (Schwartz, Cancer Res. 39: 1129-1132, 1979). Moreover, the risk of developing bladder cancer was found to be increased in men having lower serum DHEA levels (Gordon et al., Cancer Res. 51: 1366-1369, 1991).
U.S. patent application U.S. 5,550,107 relates to a method of treatment of breast and endometrial cancer in susceptible warm-blooded animals which may include inhibition of ovarian hormonal secretion by surgical means (ovariectomy) or chemical means (use of an LHRH agonist, e.g. [D-Trp6, des-Gly-NH210]LHRH ethylamide, or antagonist) as part of a combination therapy. Antiestrogens, androgens, progestins, inhibitors of sex steroid formation (especially of 17xcex2-hydroxysteroid dehydrogenase- or aromatase-catalyzed production of sex steroids), inhibitors of prolactin secretion and of growth hormone secretion and ACTH secretion are discussed. A counterpart thereof has been published under international publication number WO 90/10462.
In addition, cardiovascular diseases have been associated with decreased serum levels of DHEA and DHEA-S and both DHEA and DHEA have been suggested to prevent or treat these conditions (Barrett-Connor et al., N. Engl. J. Med. 315: 1519-1524, 1986).
In aged Sprague-Dawley rats, Schwartz (in Kent, Geriatrics 37: 157-160, 1982) has observed that body weight was reduced from 600 to 550 g by DHEA without affecting food intake. Schwartz (Cancer 39: 1129-1132, 1979) observed that C3H mice given DHEA (450 mg/kg, 3 times a week) gained significantly less weight and grew older than the control animals, had less body fat and were more active. The reduction in body weight was achieved without loss of appetite or food restriction. Furthermore, DHEA could prevent weight gain in animals bred to become obese in adulthood (in Kent, Geriatrics 37: 157-160, 1982).
DHEA administration to lean Zucher rats decreased body weight gain despite increased food intake. Treated animals had smaller fat pads thus, overall, suggesting that DHEA increases food metabolism, resulting in lower weight gain and fat accumulation (Svec et al., Proc. 2nd Int. Conf. Cortisol and Anti-Cortisols, Las Vegas, Nev., USA, p. 56 abst., 1997).
Obesity was found to be improved in the Avy mutant mouse (Yen et al., Lipids 12: 409-413, 1977) and in the Zucker rat (Cleary and Zisk, Fed. Proc. 42: 536, 1983). DHEA-treated C3H mice had a younger appearance than controls (Schwartz, Cancer Res. 39: 1129-1132, 1979). DHEA reduced the incidence of atherosclerosis in cholesterol-fed rabbits (Gordon et al., J. Clin. Invest. 82: 712-720, 1988; Arad et al., Arteriosclerosis 9: 159-166, 1989). Moreover, high serum concentrations of DHEA-S have been reported to protect against death from cardiovascular diseases in men (Barrett-Connor et al., N. Engl. J. Med. 315: 1519-1524, 1986). Circulating levels of DHEA and DHEA have thus been found to be inversely correlated with mortality from cardiovascular disease (Barrett-Connor et al., N. Engl. J. Med. 315: 1519-1524, 1986) and to decrease in parallel with the diminished immune competence (Thoman and Weigle, Adv. Immunol. 46: 221-222, 1989). A study in man has shown an inverse correlation between fetal serum DHEA-S and low density lipoprotein (LDL) levels (Parker et al., Science 208: 512, 1980).
Uses of DHEA as well as the benefits of androgen and estrogen therapy are discussed in International Patent Publication WO 94/16709.
Correlations observed in the prior art are not believed to suggest treatment or prophylactic methods that are effective, or as free of undesirable side-effects, as are combination therapies disclosed here.
It is accordingly an object of the present invention to provide effective methods of treatment for osteoporosis, hypercholesterolemia, hyperlipidemia, atherosclerosis, breast cancer, endometrial cancer, ovarian cancer and uterine cancer while minimizing undesirable side effects.
It is another object to provide methods of reducing the risk of acquiring the above diseases.
It is another object to provide kits and pharmaceutical compositions suitable for use in the above methods.
In one embodiment, the invention pertains to a method of treating or reducing the risk of acquiring osteoporosis comprising increasing levels of a sex steroid precursor selected from the group consisting of dehydroepiandrosterone (DHEA), dehydroepiandrosterone-sulfate (DHEA) and androst-5-ene-3xcex2,17xcex2-diol (5-diol), in a patient in need of said treatment or said reduction, and further comprising administering to said patient a therapeutically effective amount of a selective estrogen receptor modulator (SERM) as part of a combination therapy.
In another embodiment, the invention provides a method of treating or reducing the risk of acquiring hypercholesterolemia comprising increasing levels of a sex steroid precursor selected from the group consisting of dehydroepiandrosterone, dehydroepiandrosterone-sulfate and androst-5-ene-3xcex2,17xcex2-diol, in a patient in need of said treatment or said reduction, and further comprising administering to said patient a therapeutically effective amount of a selective estrogen receptor modulator as part of a combination therapy.
In another embodiment, the invention provides a method of treating or reducing the risk of acquiring hyperlipidemia comprising increasing levels of a sex steroid precursor selected from the group consisting of dehydroepiandrosterone, dehydroepiandrosterone-sulfate and androst-5-ene-3xcex2,17xcex2-diol , in a patient in need of said treatment or said reduction, and further comprising administering to said patient a therapeutically effective amount of a selective estrogen receptor modulator as part of a combination therapy.
In another embodiment, the invention provides a method of treating or reducing the risk of acquiring atherosclerosis comprising increasing levels of a sex steroid precursor selected from the group consisting of dehydroepiandrosterone, dehydroepiandrosterone-sulfate and androst-5-ene-3xcex2,17xcex2-diol , in a patient in need of said treatment or said reduction, and further comprising administering to said patient a therapeutically effective amount of a selective estrogen receptor modulator as part of a combination therapy.
In another embodiment, the invention provides a method of treating or reducing the risk of acquiring breast cancer comprising increasing levels of a sex steroid precursor selected from the group consisting of dehydroepiandrosterone, dehydroepiandrosterone-sulfate and androst-5-ene-3xcex2,17xcex2-diol , in a patient in need of said treatment or said reduction, and further comprising administering to said patient a therapeutically effective amount of a selective estrogen receptor modulator as part of a combination therapy.
In another embodiment, the invention provides a method of treating or reducing the risk of acquiring endometrial cancer comprising increasing levels of a sex steroid precursor selected from the group consisting of dehydroepiandrosterone, dehydroepiandrosterone-sulfate and androst-5-ene-3xcex2,17xcex2-diol , in a patient in need of said treatment or said reduction, and further comprising administering to said patient a therapeutically effective amount of a selective estrogen receptor modulator as part of a combination therapy.
In another embodiment, the invention provides a method of treating or reducing the risk of acquiring uterine cancer comprising increasing levels of a sex steroid precursor selected from the group consisting of dehydroepiandrosterone, dehydroepiandrosterone-sulfate and androst-5-ene-3xcex2,17xcex2-diol , in a patient in need of said treatment or said reduction, and further comprising administering to said patient a therapeutically effective amount of a selective estrogen receptor modulator as part of a combination therapy.
In another embodiment, the invention provides a method of treating or reducing the risk of acquiring ovarian cancer comprising increasing levels of a sex steroid precursor selected from the group consisting of dehydroepiandrosterone, dehydroepiandrosterone-sulfate and androst-5-ene-3xcex2,17xcex2-diol , in a patient in need of said treatment or said reduction, and further comprising administering to said patient a therapeutically effective amount of a selective estrogen receptor modulator as part of a combination therapy.
In another embodiment, the invention provides a kit comprising a first container containing a therapeutically effective amount of at least one sex steroid precursor selected from the group consisting of dehydroepiandrosterone, dehydroepiandrosterone-sulfate, androst-5-ene-3xcex2,17xcex2-diol and any prodrug that is converted in vivo into any of the foregoing precursors; and further comprising a second container containing a therapeutically effective amount of at least one selective estrogen receptor modulator.
In another embodiment, the invention provides a pharmaceutical composition comprising: a) a pharmaceutically acceptable excipient, diluent or carrier; b) a therapeutically effective amount of at least one sex steroid precursor selected from the group consisting of dehydroepiandrosterone, dehydroepiandrosterone-sulfate, androst-5-ene-3xcex2,17xcex2-diol and a prodrug that is converted in vivo into any of the foregoing sex steroid precursors; and c) a therapeutically effective amount of at least one selective estrogen receptor modulator.
As used herein, a selective estrogen receptor modulator (SERM) is a compound that either directly or through its active metabolite functions as an estrogen receptor antagonist (xe2x80x9cantiestrogenxe2x80x9d) in breast tissue, yet provides estrogenic or estrogen-like effect on bone tissue and on serum cholesterol levels (i.e. by reducing serum cholesterol). Non-steroidal compounds that function as estrogen receptor antagonists in vitro or in human or rat breast tissue (especially if the compound acts as an antiestrogen on human breast cancer cells) is likely to function as a SERM. Conversely, steroidal antiestrogens tend not to function as SERMs because they tend not to display any beneficial effect on serum cholesterol. Non-steroidal antiestrogens we have tested and found to function as SERMs include EM-800, EM-01538, Raloxifene, Tamoxifen and Droloxifene. We have tested the steroidal antiestrogen ICI 182,780 and found not to function as SERMs. SERMs in accordance with the invention may be administered in the same dosage as known in the art when these compounds are used as antiestrogens.
We have also noted a correlation between the beneficial effect SERMs have on serum cholesterol and beneficial estrogenic or estrogen-like effects on bone and on serum lipids. SERMs that have been shown in our research to act beneficially on all of these parameters, include bone mass, cholesterol, and triglyceride levels. Without intending to be bound by theory, it is believed that SERMs, many of which preferably, have two aromatic rings linked by one to two carbon atoms, are expected to interact with the estrogen receptor by virtue of the foregoing portion of the molecule that is best recognized by the receptor. Preferred SERMs have side chains which may selectively cause antagonistic properties in breast tissue without having significant antagonistic properties in other tissues. Thus, the SERMs may desirably functions as antiestrogens in the breast while surprisingly and desirably functioning as estrogens (or providing estrogen-like activity) in bone and in the blood (where concentrations of lipid and cholesterol are favorably affected). The favorable effect on cholesterol and lipid translates to a favorable effect against atherosclerosis which is known to be adversely, affected by improper levels of cholesterol and lipid.
All of the diseases treated by the invention as discussed herein respond favorably to androgens. Rather than utilizing androgens per se, applicants utilize sex steroid precursors such as DHEA, DHEA-S, 5-diol, or prodrugs converted to any such sex steroid precursors. In vivo, DHEA-S is converted to DHEA which in turn converts to 5-diol. It is believed that any tissue responding favorably to one is likely to respond favorably to the others. Prodrug forms of active metabolites are well known in the art. See, e.g. H. Bundgaard xe2x80x9cDesign and Application of Prodrugsxe2x80x9d (In: A Textbook of Drug Design and Development. Edited by H. Bundgaard and P. Krogsgaard-Larsen; Harwook Academic Publishers GmfH, Chur: Switzerland, 1991), the contents of which are incorporated herein by reference. In particular, see pages 154-155 describing various functional groups of active metabolites and appropriate corresponding prodrug groups that convert in vivo to each functional group. Where a patient"" levels of sex steroid precursors are raised in accordance with the invention, that may typically be accomplished by administering such a precursor or by administering a prodrug of such a precursor. By utilizing precursors instead of androgens, undesirable androgenic activity in tissues other than the target is reduced. Tissues convert precursors such as DHEA to androgens only through a natural and more regulated process. A large percentage of androgens are locally produced in peripheral tissues and to different extents in different tissues.
The cancers treated in accordance with the invention respond adversely to estrogenic activity. On the other hand, osteoporosis, hypercholesterolemia, hyperlipidemia, and atherosclerosis respond favorably to estrogenic or estrogen-like activity. By using SERMs in accordance with the invention, desirable effects are provided in target tissues without undesirable effects in certain other tissues. For example, a SERM can have favorable estrogenic effect in the bone (or on lipid or cholesterol) while avoiding unfavorable estrogenic effect in the breast.
Thus both precursor and SERM provide favorable effect in target tissues while minimizing unfavorable effects in certain other tissues. Moreover, there are substantial synergies in using the two together in accordance with the invention. For example, estrogens and androgens provide beneficial effect against osteoporosis by different mechanisms (estrogen reducing bone resorption, androgen contributing to bone formation). The combination of the present invention provides bone with beneficial estrogen or estrogen-like effect through the activity of SERM, and also provides beneficial androgen through local conversion of precursor to androgen in the bone. Precursor is also believed to provide estrogen. The same is true in connection with controlling lipid or cholesterol (useful for treating or preventing atherosclerosis). A similar synergy is provided against breast, endometrial, ovarian or uterine cancer where the SERM provides desirable antiestrogenic effect and the precursor provides desirable androgenic effect (with any incidental conversion of precursor to estrogen being mitigated by the antiestrogen). Undesirable effects are also mitigated in a synergistic way by the combination used in the invention. For all diseases discussed herein, any other effect on breast tissues that might otherwise result from estrogens produced by the precursor (when the precursor is used for promoting androgenic effects in accordance with the invention) is mitigated by the antiestrogenic effect of the SERM in breast tissue.
In some embodiments, progestins are added to provide further androgenic effect. Progestins may be used at low dosages known in the art without adversely affecting receptors other than the androgen receptors (e.g. glucocorticoid receptors). They also are relatively free of unwanted androgenic side effects (such as facial hair with female patients).
Preferred SERMs discussed herein relate: (1) to all diseases stated to be susceptible to the invention; (2) to both therapeutic and prophylactic applications; and (3) to preferred pharmaceutical compositions and kits.
In one embodiment, the precursor is DHEA.
In another embodiment, the precursor is DHEA-S.
In another embodiment, the precursor is 5-diol.
A patient in need of treatment or of reducing the risk of onset of a given disease is one who has either been diagnosed with such disease or one who is susceptible to acquiring such disease.
Except where otherwise stated, the preferred dosage of the active compounds (concentrations and modes of ad administration) of the invention is identical for both therapeutic and prophylactic purposes. The dosage for each active component discussed herein is the same regardless of the disease being treated (or of the disease whose likelihood of onset is being reduced).
Except when otherwise noted or where apparent from context, dosages herein refer to weight of active compounds unaffected by pharmaceutical excipients, diluents, carriers or other ingredients, although such additional ingredients are desirably included, as shown in the examples herein. Any dosage form (capsule, tablet, injection or the like) commonly used in the pharmaceutical industry is appropriate for use herein, and the terms xe2x80x9cexcipientxe2x80x9d, xe2x80x9cdiluentxe2x80x9d, or xe2x80x9ccarrierxe2x80x9d include such nonactive ingredients as are typically included, together with active ingredients in such dosage forms in the industry. For example, typical capsules, pills, enteric coatings, solid or liquid diluents or excipients, flavorants, preservatives, or the like may be included.
All of the active ingredients used in any of the therapies discussed herein may be formulated in pharmaceutical compositions which also include one or more of the other active ingredients. Alternatively, they may each be administered separately but sufficiently simultaneous in time so that a patient eventually has elevated blood levels or otherwise enjoys the benefits of each of the active ingredients (or strategies) simultaneously. In some preferred embodiments of the invention, for example, one or more active ingredients are to be formulated in a single pharmaceutical composition. In other embodiments of the invention, a kit is provided which includes at least tow separate containers wherein the contents of at least one container differs, in whole or in part, from the contents of at least one other container with respect to active ingredients contained therein.
Combination therapies discussed herein also include use of one active ingredient (of the combination) in the manufacture of a medicament for the treatment (or risk reduction) of the disease in question where the treatment or prevention further includes another active ingredient of the combination in accordance with the invention. For example in one embodiment, the invention provides the use of a SERM in the preparation of a medicament for use, in combination with a sex steroid precursor selected from the group consisting of DHEA, DHEA-S, 5-diol, and pro-drugs converted to any of the foregoing sex steroid precursors, in vivo, in the treatment of any of the diseases for which the present combination therapy is believed effective (i.e., breast cancer, endometrial cancer, uterine cancer, ovarian cancer, osteoporosis, hypercholesterolemia, hyperlipidemia, and atherosclerosis). In another embodiment, the invention provides the use of a sex steroid precursor selected from the group consisting of DHEA, DHEA-S, 5-diol, and pro-drugs converted to any of the foregoing sex steroid precursors, in vivo, in the preparation of a medicament for use, in combination with a SERM, for treatment of any of those same diseases.
In one embodiment of the invention, DHEA is not utilized as the precursor. In another embodiment, EM-800 is not used as the SERM In another embodiment, the combination of DHEA with EM-800 is not used.
In one preferred embodiment, DHEA is used in combination with EM-1538.